Marathon nuclear talks continue in the Austrian capital of Vienna as Iran and the P5+1 group of countries hold a second plenary session to settle the last hurdles blocking a final nuclear deal.

Iranian Foreign Minister Mohammad Javad Zarif sat down with his counterparts from the P5+1 countries and EU foreign policy chief Federica Mogherini in Vienna for the second time on Monday amid speculations that the deadline to reach a comprehensive agreement might be extended.

Earlier on Monday, the foreign ministers of the United Nations Security Council’s five permanent members and Germany took part in a coordination meeting on Iran’s nuclear case in Vienna.

The meeting was held behind closed doors without representatives from Tehran.

The Iranian foreign minister and US Secretary of State John Kerry have reportedly held 15 rounds of meetings over the last 10 days in Vienna.

Zarif held separate one-on-one meetings with his Russian counterpart Sergei Lavrov and Mogherini on Monday.

Iran and the six world powers – the United States, Britain, France, Russia, China and Germany – have been engaged in sensitive nuclear talks over the past 10 days in the Austrian capital to nail down a landmark deal over Tehran’s nuclear program.

'Serious differences remain'

A source close to the Iranian nuclear negotiating team said on Monday that “serious differences” still exist between Iran and the P5+1 countries.

“Today’s negotiations showed that differences are serious but the two sides are also firmly determined to settle the differences,” IRNA quoted the source as saying.



[caption id="" align="alignnone" width="555"] Iranian Foreign Minister Mohammad Javad Zarif (R) and EU foreign policy chief Federica Mogherini attend a meeting at the Palais Coburg Hotel, the venue of nuclear talks between Iran and the P5+1, in Vienna, Austria, on July 6, 2015. © AFP[/caption]

Iran insists on red lines

A member of the Iranian negotiating team said on Monday that Iran would never cross its red lines in the nuclear talks with the P5+1.

He told reporters that Iranian negotiators seek to strike a “good deal” with the six world powers and are ready to remain at the negotiating table until such an agreement is reached between the two sides.

Possible extension of talks

White House spokesman Josh Earnest said on Monday that the extended July 7 deadline for a final deal between Iran and the global powers could further "slip”.

"I would say that it's certainly possible," he said after the two sides missed a June-end deadline pushing the Vienna negotiations into the first week of July.

However, he did not “set any expectations at this point”, saying, "This [July 7] is the deadline that we continue to operate against, and that reflects the rather aggressive pace of the negotiations that are underway right now."

By Press TV